Flash processing of an AISI8620 steel sheet, which involves rapid heating and cooling with an overall process duration of <10 s, produced a steel microstructure with a high tensile strength and good ductility similar to that of advanced high strength steels. Flash processed steel [ultimate tensile strength (UTS): 1694 MPa, elongation: 7·1], showed at least 7 higher UTS and 30 greater elongation than published results on martensitic advanced high strength steel (UTS: 1585 MPa, elongation: 5·1). The underlying microstructure was characterised with optical, scanning electron, transmission electron microscopy as well as hardness mapping. A complex distribution of bainitic and martensite microstructures with carbides was observed. A mechanism for the above microstructure evolution is proposed.
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